Ivabradine reduces heart rate without affecting contractility or blood pressure. Its target is:

• A L-type calcium channels in sinoatrial node
• B Beta-1 adrenoceptors in the sinoatrial node
• C Delayed rectifier potassium channels (IKr) in the sinoatrial node
• D HCN (funny current, If) channels in the sinoatrial node ✓

Explanation

Ivabradine selectively and specifically inhibits the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels that carry the funny current (If) in the sinoatrial node. If is the principal current driving spontaneous diastolic depolarization; blocking it slows the slope of phase 4 depolarization and reduces heart rate. Because it does not affect contractility, AV conduction, or peripheral vascular tone, it is particularly useful in HFrEF patients intolerant of beta-blockers.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.